Advanced manufacturing, also referred to as additive manufacturing, may be used to quickly and efficiently manufacture complex three-dimensional components layer-by-layer, effectively forming the complex component. Such advanced manufacturing may be accomplished using polymers, alloys, powders, solid wire or similar feed stock materials that transition from a liquid or granular state to a cured, solid component.
Polymer-based advanced manufacturing is presently accomplished by several technologies that rely on feeding polymer materials through a nozzle that is precisely located over a preheated polymer substrate. Parts are manufactured by the deposition of new layers of materials above the previously deposited layers. Unlike rapid prototyping processes, advanced manufacturing is intended to produce a functional component constructed with materials that have strength and properties relevant to engineering applications. On the contrary, rapid prototyping processes typically produce exemplary models that are not production ready.
In general, advanced manufacturing selectively adds material in a layered format enabling the efficient fabrication of incredibly complex components. Unlike subtractive techniques that require additional time and energy to remove unwanted material, advanced manufacturing deposits material only where it is needed making very efficient use of both energy and raw materials. This can lead to significant time, energy, and cost savings in the manufacture of highly advanced components for the automotive, biomedical, aerospace and robotic industries. In a heretofore separate process, carbon fiber layups used in laminated composite parts are generally made in a labor intensive process in which aligned carbon fibers or carbon fiber sheets are laid layer by layer into a cavity of a mold or around a mandrel. Once the carbon fiber layup is achieved, the carbon fibers and/or sheets of carbon fiber are typically bonded together by a resin or epoxy such that in the final product the carbon fiber is surrounded by the resin and joined to each other. Such embedded fibers are responsible for the stiffness and the loading capacity of the final product whereby the resin supports the fibers laterally.
Both advanced manufacturing techniques and production processes for composite materials generally rely on large ovens or autoclaves for curing thereby constraining the size of the component to be manufactured. In addition, both processes may require movement of the part in process from buildup to curing to layup, thus endangering the integrity of the final build.
In addition, the utilization of an oven or autoclave introduces many limitations. First, the oven requires significant power, especially for higher temperature and larger parts. If materials change, it also takes time to get the oven up to the proper operating temperature. Temperature gradients within the oven introduce distortions and dimensional variability in parts as well. Variations in parts may occur depending upon where in the oven a part is manufactured.
Another constraint introduced by the oven, autoclave or heated bed is a limitation on the build envelope size. Conventional build systems using ovens typically require a limited build size of 36″×36″×24″. As such, the resulting builds must fit within this envelope or be constructed in assembled stages thereby increasing complexity and cost and limiting strength and engineering flexibility.